Lower Limit

ECM-261A LONG-TERM FUEL TRIM
LOWER LIMIT

Checking fuel injection system



Check intake system for air leakage according to Check For Air Leaks In the Intake System

Hint: Air leakage in the intake system can occur through the canister purge (CP) valve, the secondary air solenoid valve and power brake booster.

Check the exhaust system for air leakage according to Checking For Air Leakage In the Exhaust System

Check fuel pressure according to Checking Fuel and Residual Pressures

Check that the oil level is between the minimum and maximum markings

Check engine dilution by, reading off the short-term fuel trim with the engine running, plug the crankcase ventilation and read off the short-term fuel trim again, the value should be more or less unchanged

Remedy as necessary.

Was a fault detected?
Yes - Skip to "Verification"
No - Continue below.


Checking mass air flow (MAF) sensor



Test drive the car for approximately 10 minutes.
Read the mass air flow (MAF) sensor correction factor. The value must be between 0.8 and 1.2

NOTE: There must not be any air leakage when this test is carried out.

Remedy as necessary.

Other information:
- To access/replace the Mass Air Flow (MAF) sensor, Mass Air Flow (MAF) Sensor, Replacing


Verification



Test drive the car according to the TRIP schedule, Monitors, Trips, Drive Cycles and Readiness Codes
Do not turn off engine after test drive.
Connect the car to VIDA again.
Read fuel trim status.
There should not be any faults when fuel trim is finished.

Was a fault detected?
Yes - Continue below.
No - Testing Complete.


Fault-tracing information
The fault should have been detected and remedied. As this is not the case fault-tracing has failed. Exit fault tracing for this diagnostic trouble code (DTC) or make another attempt.